In the prior art, there is an optical waveguide device in which optical waveguides which handle light signals are formed on a wiring substrate which handles electric signals. The optical waveguide device is an optoelectronic composite substrate, in order to compensate the limit of the transmission speed of the electric signals, the high speed parts can be transmitted by the light signals.
A light path conversion mirror is arranged on an edge side of the optical waveguide, and an optical element is mounted on the wiring substrate so as to be optically coupled to the light path conversion mirror of the optical waveguide.
A related art is disclosed in Japanese Laid-open Patent Publication No. 2005-136347, Japanese Laid-open Patent Publication No. 2008-111990, and Japanese Laid-open Patent Publication No. 2013-186310.